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Battery electric vehicles (BEVs) and fuel cell electric vehicles (FCEVs) have been identified as two electromobility options which can help to achieve GHG emission reduction targets in the transport sector. However, both options will also impact the future energy system characterized by integration of various demand sectors and increasing intermittent power generation. The objective of this paper is to examine the optimal mix of both propulsion systems and to analyze the cost for renewable fuel supply. We propose a generic approach for dimensioning of fast charging and hydrogen refueling stations and optimization of the fuel supply system. The model is applied in a case study for passenger cars on German highways. The results indicate that a parallel build-up of stations for both technologies does not increase the overall costs. Moreover, the technology combination is also an optimal solution from the system perspective due to synergetic use of hydrogen but limited efficiency losses. Hence, BEVs and FCEVs should jointly contribute to the decarbonization of the future energy system.

This paper analyzes the impact of hydrogen as energy storage on production and investment decisions in an electricity market when individual participants behave strategically. We develop a game-theoretic model on investment and generation game a la Cournot under the open-loop information structure. This framework is implemented as a mixed complementarity problem and applied to the German case assuming the phase-out of the German nuclear power plants, rising renewable energy supply and increasing energy demand for electric vehicles. The numerical results of our analysis indicate that utilization of energy storage has a positive effect on energy systems with large amount of intermittent electricity and inelastic demand. We find that additional hydrogen storage capacities improve system reliability, increase overall welfare and decrease GHG emissions. Adding demand for hydrogen as a fuel for FCEVs allows for a synergetic use of the technology and changes the investment incentives for energy storage. Although the power-to-gas technology has a price-smoothing effect the overall generation capacity is higher with energy storage providing additional supply security in markets with a large amount of intermittent energy production.

The introduction of the hydrogen refueling stations infrastructure is a complex issue not only from the technological but also economic perspective. The paper focuses on the impact of transfer prices between different steps of the hydrogen value chain on the financial results of potential investors. Assuming a given selling price to the consumer, such transfer prices can be seen as an instrument for the allocation of financial risks and rewards between investors. However, asymmetric information may lead to conflicting objectives and insufficient design of the entire infrastructure. The paper presents also financial outcomes of an infrastructure analysis in Berlin and Hamburg. Based on the results of an infrastructure simulation respective revenues and costs for investors are determined. Assuming specific hydrogen prices the study shows that the design of the pricing system has major impact on the financial situation of single actors and consequently on the success of the hydrogen initiative.

The use of O-arylphosphoroamidites in the synthesis of nucleosides phosphates of biological interest and their P–F analogues is described. This goal is achieved by extremely smooth reaction of O-arylphosphites with fluoride anion donors. Dinucleoside phosphorofluoridites RO(R′O)PF prepared by this method can be resolved into diastereoisomeric forms. Phosphorofluoroamidites –P(F)NR2 are efficient reagents in the synthesis of corresponding esters –P(F)OR′. These P(III)–F systems are employed in a new and effective synthesis of trifluoromethylphosphonite P(III)–CF3 by reaction with (trifluoromethyl)trimethylsilane (CF3SiMe3). This reaction, catalysed by the fluoride anion, can be part of a sequential procedure that combines formation of P(III)–F compounds with their transformation into the corresponding P(III)–CF3 system. To cite this article: J. Michalski et al., C. R. Chimie 7 (2004).

A new convenient and general procedure is described for the preparation of mixed phosphites from readily available phosphorofluoroamidites by stepwise replacement of amino and fluoro-groups in the presence of trimethylchlorosilane (Me 3 SiCl). The reaction mechanism is briefly discussed.

2,4-Dinitrophenol (DNP) is a remarkably efficient activator in the reaction of P(III) amides with nucleosides to give P(III) esters in excellent yield. Typical examples of this novel procedure are presented herein. Mechanistic features of the activation were elucidated by model studies of the reaction of bis(2-cyanoethyl)diisopropylphosphoroamidite with benzyl alcohol. The importance of the initial protonation stage and formation of an intermediate P(III)-2,4-dinitrophenyl ester were clearly demonstrated by 31 P NMR spectroscopy and independent synthesis. New phosphitylating reagents containing the 2,4-dinitrophenoxy group do not require any activation.

The reactions of azetidinium salts with phosphorus nucleophiles R2P(O)H have been investigated. Treatment of O-benzyl-N,N-diethyl-3-hydroxyazetidinium salt 2 with R2P(O)H in the presence of sodium hydride gave the corresponding γ-N,N-diethylamino-β-benzyloxypropylphosphonate 6a or phosphine oxide 6b. After debenzylation γ-N,N-diethylamino-β-hydroxypropylphosphonate 3a and phosphine oxide 3b were obtained. The compound 6a was converted into its sulfonate ester 8 which underwent elimination to yield 4. The structure 4 has been employed in Michael addition of R2P(O)H to form compounds 5 containing two phosphorus centers. Further compounds of type 3 have been transformed into compounds 5 by reaction with R2P(O)H in the presence of 1.1 equivalents of NaH in boiling toluene. Finally, azetidinium salts 1 have been converted into compounds 5a by reaction with two equivalents of R2P(O)H in the presence of 2.1 equivalents of NaH. Molecular mechanics with implementation of the Allinger MM2 force field and semiempirical AM1 and PM3 methods were used to investigate structures 5d and 5f.

A stereospecific synthesis of P-chiral sulfenyl chlorides 6a,b has been developed from P-chiral sulfenylamide 9a,b,c by a novel procedure employing 2Me 3 SiCl + 2EtOH as the reagent of choice. The sulfenylamides 9a,b,c were prepared either by stereospecific reaction of the P-chiral hydrogen phosphinothioate 8a with aminosulfenyl halides or separation of a mixture of diastereomeric 9a,b,c by crystallisation. P-Chiral chlorides 6a,b were allowed to react with secondary amines such as morpholine or dicyclohexyl amine. All these displacement reactions proceed with almost complete stereochemical integrity at the phosphorus atom. These abservations support a synchronous mechanism of bond breaking and bond formation during nucleophilic displacement at the dicoordinate sulfur atom. The same can be said about the reaction of sulfenamides 9a,b,c with hydrogen chloride.

The reaction of perbenzylated (±)-myo-inositol 1,2-bis- and 1,2,6-tris-phosphites with benzyl bromoacetate, followed by catalytic ( Pd C ) hydrogenolysis affords (±)-myo-inositol 1,2-bis- and 1,2,6-tris(carboxymethylphosphonate). The same procedure is used for the synthesis methyl α-D-mannopyranoside 2,3,4-tris(carboxymethylphosphonate).

Novel and efficient synthesis of polyfunctional γ- and δ-aminophosphonic acids derivatives via ring opening of 3-alkoxyazetidinium salts with phosphorus containing nucleophiles is described.

Reaction of phosphorus acids bromides and iodides with silver salts of sulfonic acids leads to the formation of mixed phosphorus and sulfonic acids anhydrides 3 in excellent yield. This method allowed the first synthesis of mixed anhydrides containing a P-chiral centre; they were subsequently separated into pure diastereoisomers.

The reaction of readily available dialkyltrimethylsilyl phosphites (RO)2POSiMe3 5 with sulfur dichloride leads to tetra-alkyl sym-monothio-pyrophosphates (RO)2P(O)SP(O)(OR)2 1 in high yield. The method is suitable for the synthesis of tetra t-butyl thiopyrophosphate 1d.

A new synthetic approach to modified oligonucleotides based on N,N′-diisopropyl-di-(4-nitrophenyl)phosphoroamidite 1 is described. The procedure involves displacement of either 4-nitrophenoxy or diisopropylamino ligands. The former proceeds very fast in the presence of DBU, the latter requires activation by tetrazole. This method allows rapid and almost quantitative construction of modified nucleotides derived from thio- and selenophosphorus acids.

First example of the PIII coupling reagent containing 4-nitrophenoxy group is described. Its usefulness is demonstrated by synthesis of dinucleoside methylphosphonate and methylthiophosphonate.

Trifluoroacetic anhydride reacts with organophosphorus compounds containing thiophosphoryl and selenophosphoryl groups converting them in high yield to the corresponding oxygenated systems.

Stereoselective synthesis of phosphocarnitine has been achieved for the first time starting from R(−)-epichlorohydrin.

The azolides of general formula 1 are readily available 1 and can be transformed in quantitative way by acyl fluorides or oxalyl fluoride into the corresponding P- fluorides 2. This strategy was extended towards synthesis of difluorides R-P(X)F 2 and trifluorides P(X)F 3 . The method was also successfully applied in chemistry of P-F modified nucleotides. e.g.

The reaction of acyclic oxophosphoranesulphenyl chlorides, with phosphorus trichloride has been found to give thiophosphoryl chlorides, and phosphoryl oxychloride—the products of the exclusive deoxygenation of sulphenyl chloride. Optically active phosphonochloridothionates and phosphorochloridothionates in a high state of optical purity have been obtained with inversion of configuration from optically active sulphenyl chlorides and phosphorus trichloride. It has been shown, however, that cyclic oxophosphoranesulphenyl chlorides undergo simultaneous desulphurisation and deoxygenation when treated with phosphorus trichloride. Using cis- and trans-isomers of 2-chlorothio-4-methyl-1,3,2-dioxaphosphorinan-2-one it has been demonstrated that deoxygenation is accompanied by inversion, whereas desulphurisation occurs with retention at phosphorus. The mechanism of the title reaction is discussed.

The reaction of the individual diastereoisomeric cyclic phosphorothioates 2a , 2b in the trans-2,4,7-trioxa-3-phosphabicyclo (4.4.0) decane and 4a , 4b in the trans-2,4,7-trioxa-3-phosphabicyclo (4.3.0) nonane series with sulphuryl chloride affords the corresponding sulphenyl chlorides 5a , 5b , 6a , 6b with retention of the configuration of the phosphorus atom. The reaction of the latter with phosphorus trichloride leads stereospecifically to the chlorophosphates 7a , 7b , 8a and 8b with full retention of configuration at phosphorus.

The thiocyanation of organophosphorus compounds containing >P(X)H functional group (X = O, S) has been reinvestigated. The reaction wa shown to be highly stereospecific and proceeds with the retention of configuration at P via the thiocyanidate >P(O)SCN structure. The thiocyanidates rearrange into the isothiocyanidates >P(O)NCS with a rate of depending on structure of substrates and reaction conditions. The thiocyanation reaction of dialykl phosphite and their structural analogues offers an excellent route to the isothicyanidates >P(X)NCS and in some cases also to the thiocyanidates >P(X)SCN.

Optically active t-butylphenylphosphinothiocyanidate Bu t PhP(O)SCN 3 and t-butyl-O-methyl-phosphonothiocyanidate Bu t (MeO)P(O)SCN 7 have been prepared by condensation of the corresponding sulphenyl chlorides > P(O)SCl with trimethylsilylcyanide and isomerised into optically active t-butyl-O-methyl-phos-phonoisothiocyanidates Bu t (MeO)P(O)NCS 8 . Chirality at P in and the optical purity of the chiral phosphino (phosphono) thiocyanidates and isothiocyanidates have been determined by chemical correlations. It has been demonstrated that the thiocyanate ion and amine catalysed thiocyanidate-isothiocyanidate isomerisation > P(O)SCN → > P(O)NCS occurs stereospecifically with inversion of configuration at the P center. This result can be rationalized by postulation of a phosphorane intermediate, formed by nucleophilic attack of the SCN - anion on phosphorus, in which thiocyanate and isothiocyanate groups occupy apical positions. In connection with these studies a number of novel optically active phosphorylated derivatives of carbonic acid, > P(O)NHCSNHR, > P(O)NCCl 2 , > P(O)NCO and > P(O)NHCOOBu t , have also been synthesised.

The reaction of a trialkyl phosphite with trimethylsilyl iodide, which leads to O -trimethylsilyl esters of alkylphosphonic acid, has been shown to involve several steps, all of which are defined. The first step is the formation of the iodophosphite, involving a four centre mechanism in which P III plays the role of electrophile. This is in contrast to the analogous reaction of phosphates with alkyl halides (the Arbuzov reaction) which begins with nucleophilic attack of the phosphorus.

The reaction of triorganosilylsulfenyl halides R3SiSX (R  Ph, Et; X  Cl, Br) with carboncarbon double bonds, trialkyl phosphites, and organometallic reagents have been studied. With the first two nucleophiles the course of the reactions differed from that with organosulfenyl chlorides because of nucleophilic attack of halide ion on silyl group.

We report the synthesis of the first optically active silyl esters of phosphorus hewing too centres of chirality : one on silicon and the other on phosphorus. Compounds we obtained of general formula : t-BuPhP(X)YSiαNpPhMe X,Y=0,0( 1 ): S, ( 2 ); Se, 0(3); S, 3(4); doublet, 0( 5 ) including 1 and 3 with optical activity located on Si, 2 and 5 with the activity on Si or P and on both these centras, 4 only racemic. Absolute configurations are determined. 31P and-29Si NMR spectra of these models and their trimethylsilyl analogues are reported. The triorganosilyl group is always preferentially bound to phosphorus through oxygen atom. Surprisingly, diastereotopio NMR chemical shifts exclude the fast 1,3 migration in esters 1 and 4 . 29Si NMR spectra correspond to a tetracoordinate silicon atom.

Catalytic activities of R(+) and racemic t-butylphenylphosphinothioic acids on the mutarotation of 2,3,4,6 tetramethyl-d-glucose are studied in benzene.

Stable ionic 11 adducts, thought to be of the type [(Me2N)3POSiMe3]+X− have been isolated from the interaction of HMPT with the halides Me3SiX (X  Br or I). Conductometric studies show that the equilibrium for formation of these adducts in CH2Cl2 lies well over to the products for X  Br or I, but for X  Cl the equilibrium lies close to the reactants. The known kinetic characteristics of reaction involving HMPT-catalysed racemisations or substitutions of silicon halides can be interpreted in terms of the formation of such phosphonium intermediates.

A study is described of the reaction of trimethylbromosilane and trimethyliodosilane with various esters of phosphorothioic and phosphoroselenoic acids of general structures (RO) 2 (RY)P=O (I) and (RO) 3 P=Y (II) (Y = S or Se, R = alkyl). The reaction results in replacement of the R groups by trimethylsilyl groups. No S -trimethylsilyl and Se -trimethylsilyl substituted esters were found among the products. Thus the displacement of the O -R group in II as well as the replacement of S -organyl or Se -organyl groups in I both lead to the corresponding O -trimethylsilyl isomer containing thiophosphoryl or selenophosphoryl groups. The following sequence of reactivity of the ester groups was observed: Download full-size image The process involves initially the reversible formation of a phosphonium salt intermediate in a fast step, followed by slow dealkylation. It was shown by low temperature 31 P FT-NMR studies that in the reaction of trimethyliodosilane with an ester bearing a P=O phosphoryl group, the equilibrium for the phosphonium salt formation lies well over towards the intermediate and so the intermediate can be observed directly. These mechanistic proposals were confirmed by conductance studies on the reaction system and by investigation of the stereochemical course of the corresponding reaction of an optically-active model thiophosphonate. In some cases the reaction of the halosilanes with the phosphates takes a selective course which allows the reaction to be used as a convenient route to O -silyl substituted esters of phosphorothioic or phosphoroselenoic acids.

In order to throw light on the possible role of positively charged tetra-coordinate silicon intermediates in the racemization of α-NpPhMeSiCl ( 1 ) induced by uncharged nucleophiles two sets of kinetic studies have been carried out. In the first the rates of two reactions namely racemization of 1 catalysed by (PhO) 2 (Me 3 SiO)PO ( 2 ) and transsilylation of 2 with 1 , which take place together and are believed to involve the same intermediate were determined; the transsilylation was found to be faster than the racemization, and involved transient formation of an optically active product. In the second the racemization of 1 catalysed by HMPT in various CCl 4 /CH 2 Cl 2 mixtures was studied; the rate was found to increase markedly with increase in the dielectric constant of the medium. The results of both sets of experiments were consistent with a mechanism involving a silyloxyphosphonium cation intermediate.

The oxidative addition of thiocyanogen to triphenylphosphine has been investigated by 31P NMR spectroscopy showing the formation of the isothiocyanatophosphonium salt 8. The analogous reaction between thiocyanogen and alkyl o-phenylene phosphites 7 leads to diisothiocyanatophosphoranes 9. The same products were prepared via ligand substitution from the corresponding chlorophosphonium salt 12 and alkyldichloro-o-phenylene phosphoranes 13 by the action of potassium thiocyanate in the presence of 18-crown-6-ether or more conveniently using lead thiocyanate. The phosphonium salt 8 and phosphoranes 9 were employed as convenient novel reagents for converting hydroxy groups into thiocyanate and isothiocyanate functions with high stereoselectivity under very mild conditions. The efficient synthesis of acylisothiocyanales RCONCS, R2P(O)NCS and R2P(S)NCS via addition of thiocyanogen to mixed anhydrides is of special interest.

The reaction of phosphorous hexamethyltriamide with trimethylsilyl iodide or bromide provides a convenient synthesis of the corresponding N,N,N',N'-tetramethylphosphorodiamidous halide. Low temperature 31P NMR studies gave evidence of the formation of a phosphonium salt-type complex with direct P-Si bonding in the first step of the reaction. Analogous phosphonium salt intermediates involving P-P bonds were found to be involved in some ligand exchange process between two tricoordinated phosphorus species.

Optically active pyrophosphonothionates (II, III and IV) have been obtained in the reaction between optically active O-ethyl ethylphosphonothioic acid (I) and 2-chloro-2-oxo-5,5-dimethyl-1,3,2-dioxaphosphorinan, diethyl phosphorochloridate and O,O-diethyl phosphorochloridothionate respectively. It has been found that alkaline hydrolysis of these anhydrides occurs with full inversion of configuration at the thiophosphoryl centre. The reaction is discussed from the point of view of stereochemistry and the reaction mechanism.

The reaction of (−)- and (+)-O-ethyl ethylphosphonothioic acid (I) with phosphorus pentachloride has been shown to give optically active O-ethyl ethylphosphonochloridothionate (II) in high yield. For establishing the relative configuration and degree of stereospecificity of (II) use was made of the pyrophosphonothionates, prepared from I and II. The mechanism of the reaction is discussed.

Triethyl phosphite and elemental iodine in solution give transient iodotriethyl-phosphonium iodide which eliminates ethyl iodide to form diethyl phosphoroiodidate. An examination of the 31 P NMR and IR spectra over the temperature range −100° − 0°C fails to disclose any evidence for triethoxydi-iodophosphorane, contrary to a previous claim.

Phosphoroazolides, including nucleoside derivatives, can be converted smoothly into the corresponding phosphorofluoridates by reaction with benzoyl flouride. From these compounds oligonucleotides containing → P-F instead of → P-OH can be prepared.

Trimethylsilyl esters of general formula RR'POSiMe 3 derived from nucleosides react in quantitative and fully chemoselective way with sulphuryl chloride fluoride to give nucleoside fluorophosphates of high purity under extremely mild conditions.

Deselenisation of the optically active monoselenoacids lead to disubstituted phosphine oxides with high optical yield and the reaction provides a means of correlating chiral phosphorus monoselenoacids with their sulphur analogues.

Readily available nucleoside trimethylsilyl phosphites and analoguous compounds are transformed in high yield into the corresponding phosphorochloridates by reaction with sulfuryl chloride. These compounds are employed as efficient reagents for internucleotide linkage formation.